StarTalk Radio - Cosmic Queries: Answers at the Speed of Light

Episode Date: June 16, 2013

Join us for another episode of Cosmic Queries, where astrophysicist Neil deGrasse Tyson answers fan questions about light, energy and the universe as fast as comic co-host Leighann Lord can ask them. ...Subscribe to SiriusXM Podcasts+ on Apple Podcasts to listen to new episodes ad-free and a whole week early.

Transcript
Discussion (0)
Starting point is 00:00:00 Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk Radio. I'm your host, Neil deGrasse Tyson. I'm your personal astrophysicist. I hail from New York City, where I serve as director of the Hayden Planetarium of the American Museum of Natural History. And you're all invited. I got with me in studio here in New York, Leanne Lord. Leanne, welcome back.
Starting point is 00:00:41 Thank you. Love having you on the show. Good to be here. And this is the Cosmic Queries part, the Cosmic Queries sector of the universe, I like to think. And we've called questions submitted to us in all of our social media. Yes. Twitter, on our Facebook page. Email.
Starting point is 00:01:03 Email, and on StarTalkRadio.com. And so this is a hodgepodge I think Yes And I haven't seen them And you've collected them And you're going to hand them to me Yes And if I don't know the answer I'll just say I have no idea
Starting point is 00:01:11 Well I can be honest right up front I have no idea Okay So let's do this Alright Go We have a question in email That came from James Isaac Dagenhart
Starting point is 00:01:20 And he says I've read about something called Modified Newtonian dynamics. He reads a lot. That was introduced as being a possible model that doesn't presume the existence of dark matter. Does this have any credence, or is this pseudoscience sensationalism? Man, what an erudite question.
Starting point is 00:01:40 Yes. Modified Newtonian dynamics. That's otherwise known in the trade as MOND. Okay. MOND, modified Newtonian dynamics. That's otherwise known in the trade as MOND. Okay. MOND, Modified Newtonian Dynamics. And would that be an acronym? Yes, an acronym. When letters come together and you can pronounce them, right?
Starting point is 00:01:55 But the CIA is not an acronym, unless you said CIA. We actually spell out the letters. Okay. Yeah, IBM, not an acronym. Just putting that on the table. Got it. So, what, not an acronym. Just putting that on the table. Got it. So, what does he want to know? Oh, so, people don't like explaining things that we don't understand by other things that we understand less.
Starting point is 00:02:16 Okay. So, the dark matter problem in the universe, where there's six times as much gravity out there than matter enough to account for it. Right. All right. I understand. Where did it come from? And when this problem was discovered, this is now 80 years ago, it was called the missing mass problem.
Starting point is 00:02:35 There's surely some mass out there, but we can't find it. Where is it? Because I see gravity from it. And so what's the solution? It is the longest standing unsolved problem in modern astrophysics, the dark matter problem. And so, there are people who say it's not a matter problem, you just don't understand gravity. Because why do I think there's too much gravity? Because I used an equation of gravity that told me that. An equation handed to me by Isaac Newton,
Starting point is 00:03:02 Of gravity that told me that. An equation handed to me by Isaac Newton. His universal law of gravitation. Okay. So, I got his equation. I plug it in and I put in the numbers. It says the matter that's out there is not giving me as much gravity as I see. So, Mond takes, it starts out with Newton's gravity because it knows that works for most cases. But these extreme cases in galaxies and galaxy clusters, there's an extra term there.
Starting point is 00:03:26 There's an extra acceleration to account for the extra gravity brought to you by the matter that we've all known and loved. That's MOND, modified Newtonian gravity. And it has some interesting successful applications. But it doesn't explain everything. applications but it doesn't explain everything no for example we need dark matter in the early universe to explain anything we know about the formation of everything in the cosmos so uh this so they're still duking it out and if i were to vote i would say mond is on its way out but really yeah but it was there fighting for a while well i mean isn't it doesn't that what that's what science does you come up with with what's a plausible explanation at the time and you test and you test and see if it stands up.
Starting point is 00:04:08 And if it doesn't, you throw it out. There's nothing wrong with a wrong idea. Right. At the time you put it in, if it helps you try to solve a problem. One of the greatest wrong ideas ever was the geocentric universe with the earth in the middle. I thought you were going to say leg warmers. I used to have leg warmers. Oh, you better stop.
Starting point is 00:04:24 I used to wear leg warmers. You little you better stop. I used to wear leg warmers. You little flash dancer. Well, I used to dance. So I wasn't just wearing them because it was like, you know. You were chilly? Wow. Yeah, I still have them too. You are such a renaissance man.
Starting point is 00:04:36 Don't say that. And I point my toe and raise my leg. Yeah, yeah. Wow, renaissance man. Well, not anymore. That was just like long ago. But anyhow, what else you got? In a galaxy far, far away.
Starting point is 00:04:46 I have no question. You know, so Mond, there's still people working on Mond. Okay. Even though they didn't get the memo, it's on the way out. And we still don't have dark matter completely understood. So until that happens, you know, there'll be people still fighting the good fight. And that's science at its best. Yeah.
Starting point is 00:05:00 Love it. All right. I have a question from Anil Virik. And it's about lightning. Where are these people? Do we know where they from Anil Virik, and it's about lightning. Do we know where they're from? You know, Anil did not say. Okay. Oh, wait.
Starting point is 00:05:11 No, didn't say. No, didn't say. They just sent the email. Okay, just an email. All right. So right now, they're from Gmail. What country is that? That's everywhere.
Starting point is 00:05:21 Gmail is dark matter. Now, I heard lately that lasers have been used to try to direct lightning strikes. The laser is shot into the thunderhead clouds, and the plasma flows the laser back. Is there a way to harness this energy and make lightning farms? Well, first of all, that's the first I've heard of this. Oh. And I think it's amazing. And I can even explain how it works, even though I only just learned of it.
Starting point is 00:05:45 Because you're that bad. No. Because. Cue music. I need a theme. You do. You're like, you're the shaft of science. What you talk about?
Starting point is 00:05:58 Do you know I was listening to XM radio, 70s on 7, you know, because they have the 60s on 6 and 70s on 7. And on came the theme to Shaft, and I hadn't heard that in a long time. Who's the bad mother sex machine to all the chicks? And this goes on and on, and then immediately after that song, they didn't miss a beat. They played John Denver's Thank God I'm a Country
Starting point is 00:06:20 Boy. It was like, no! Hey, Mr. DJ, did you not take your meds today? No, I happen to like both songs. Well, you don't play them. This is not a mixtape. Wow. We're going to play thank God I'm a country boy after Shaft.
Starting point is 00:06:35 You could have hurt yourself on a dance floor with that. Man. Okay. Now, sorry, I distracted myself. Where were we? You did lightning for us, sir. Yeah. So here's what happens. Lightning comes about because there's a difference in charge
Starting point is 00:06:48 between a cloud and the ground beneath it. Yes. And charges don't like being separate from one another, all right? The molecules reach an excited state because they've lost their electrons. They don't like staying that way. Okay. And all the electrons are sitting on the ground, And those electrons want to get back to the cloud. And so the cloud comes over, the electrons gather, and they're ready to rise up and reach the cloud again. Thus is born a lightning strike, which tells you that lightning goes from the ground to the cloud, not the cloud to the ground.
Starting point is 00:07:21 Really? Now, so, if you take a laser that's very high power and you ionize gas at the atmosphere in one place versus another, you can build charges around where the cloud is and force a lightning bolt to go where you say so. Now, that's good. Yeah. Now, the person wants to know
Starting point is 00:07:43 if we can make a lightning farm Out of that I say Why not More of Cosmic Queries When we return We're back on StarTalk After Hours. Leanne, I shouldn't keep calling it that. No.
Starting point is 00:08:16 It's Cosmic Queries. No, I like the After Dark. You like that? Yes, it's part of the show's DNA now. Well, thank you. We keep it. How bioliterate of you. Well, you know, we're hanging out with the folks of your ilk.
Starting point is 00:08:30 If you can't be bioliterate here, you know, where can that happen? You're reading me questions. Yes. Called from the internet. And right before the break, there was a question about lightning farms. Yes. By creating spots where the lightning would strike using high-powered lasers that would ionize the air. And it's a great idea. At first I learned of it was that question, but it sounds great.
Starting point is 00:08:46 It does. You just have to watch out that your lasers aren't so powerful to ionize the air in places so that you can force a lightning discharge that you're using more energy than you get back from the lightning itself. Because then that would be inefficient. Then you're not making a light, you're not farming anything. Right, no. You're getting less than what you started with.
Starting point is 00:09:03 Now it turns out the act of forming a raindrop in a cloud takes some charge out of the cloud and brings it to the ground. Okay. So, you're relying on the sun, which evaporated the water in the first place to make the cloud, to then drop the water, bringing charges to the ground, relying on that in the first place. So, if the laser's just to help it out, to direct the lightning where it would have struck anyway, but now you strike it to your spot, your sweet spot, then you got a good farm going. I'm sorry, my what? I just had to say, I had to just clarify all of that.
Starting point is 00:09:36 Yeah. Oh, sorry. Your what? I need a moment. I think I need a cigarette. The man said my sweet spot. I didn't hear anything after that. I'm gone.
Starting point is 00:09:46 I'm just gone. I'm gone. We've got to bring it back into the show. Okay. Actually, I think we have a caller, actually. Do we really? Yes. I love it.
Starting point is 00:09:54 Yeah. So some people actually don't use the internet to bring in their questions. They actually use this old-fashioned technology called a telephone. You're going to have to explain that one. Let's find out. Caller, are you there? Yes, I am. Hello, caller. How are you today? Okay. You know my name, but I don't know your name. Well, I'm not going to tell you right away if that's okay.
Starting point is 00:10:13 Oh, okay. I actually called in to see if you could figure out what my name is. Oh, okay. All right. My dad was a physicist, a lot like yourself. He did cosmology, black holes, and all that stuff. And so my mother named the first child, so she said that he could name the second child, which is me. Uh-oh. Yeah. You're giving naming rights to the physicist in the family. That's right. These are the same people who named quarks, up, down, top, bottom, strange, and charmed.
Starting point is 00:10:42 Exactly. These are the same people who couldn't come up with a more inventive name for their super collider, but super, the super conducting super collider. It's like, you know. Which I saw on the super friends. If astro folk had, I'd call it the super duper collider, right? The physicist, I don't know if the, so have you led a disturbed life because of this? What name did you end up with? Well, I'm going to see if you can figure it out.
Starting point is 00:11:07 Okay. I think he did a little better than that. All right. Okay. So my name is Deco, D-A-C-O. D-A-C-O. What do you think that stands for? I have no idea.
Starting point is 00:11:24 Deco. Deco. Deco. But think of each letter as representing something in an equation. Something that would come out of the brain of a physicist. Okay. Give me a hint on the D. Well, let me try. Well, D could be like delta, perhaps.
Starting point is 00:11:38 Or D could be the little d as when you're taking a derivative in calculus. Oh, it is. You got the D? Okay. So DA, all right, would be a derivative of the variable A. And A could be acceleration. That's it. Oh, it is. I'm loving it.
Starting point is 00:11:56 Oh, my God. It's like a movie. Okay. It's like a Dan Brown movie. You're figuring out the pieces. However, the first derivative of acceleration is hardly ever talked about because it's called the jerk. Did you know that? It's called the jerk.
Starting point is 00:12:11 It's called the Steve Martin. So if you put on the brake in a car and then you start leaning forward, that's a constant lean. When a plane takes off on the runway, there's a constant pressure that you feel backwards. All right. So under constant acceleration, you're leaning. Right. If you change the acceleration, you jerk. Yes.
Starting point is 00:12:33 Okay. Okay. That's how you go. Got it. So if you're slowing down constantly, but then you slam on the brake, you jerk forward rather than lean forward smoothly. Okay. So the first derivative of acceleration will be the jerk. Okay.
Starting point is 00:12:47 Well, let me give you a little hint on the C. It has something to do with E equals mc squared. Well, C would clearly be the speed of light, but I don't know what dA would be, though, relative to C as the speed of light. And then I thought O could be like a little o. So I don't know, the speed of light in a vacuum perhaps. But I could, but other than that, I have no idea where he was going with this. Well, I think you answered the question because I think it's the speed of light. So the way I understand it is that D is derivative, A is acceleration,
Starting point is 00:13:23 D is a constant at an E equals mc squared, and O is zero. So I'm thinking no change in acceleration at the speed of light, and that just makes me the speed of light. But again, I'm not the physicist. I don't really know. I just have to go on faith here. What, what he didn't tell you? Well, he said it was an equation. Oh, okay. I think we still can work on this you think so let me keep work let me think about this some more i'll give you the speed of light but da
Starting point is 00:13:52 i don't know that's let me think this one through i love it that is such a great first date conversation i know it's it's always been a topic of conversation, really. That's so built in and wonderful. And just think, if I was a physicist, I would, you know, have a great name. But I'm not. I can't get my head wrapped around all that math. Me neither. I'll hook you up. It's that I'm a writer.
Starting point is 00:14:16 And I actually just debuted with my first novel. It's a thriller. It's called The Libra Affair. The Libra Affair. Yeah, and actually it's relevant to you because the hero in it is a NASA scientist. Uh-huh. Love it. And the heroine targets him.
Starting point is 00:14:31 She's a lady spy because she wants to get a hold of his laser that's going up in space with SpaceX. The chicks dig the lasers. They like the laser. He's sending it up to vap space debris, which is really relevant today. And she wants to get a hold of it to vap a missile. But, yeah, it's quite interesting, huh? Wow. Well, congratulations on that.
Starting point is 00:14:52 Yes. Thank you. Thank you. It came out, and I'm really excited, and maybe I'll do well. Well, and you're surely the only DECO in the world. That's right. You can start going solo name on this. Who needs your last name
Starting point is 00:15:09 when you have a unique first name? You know what? I'm publishing under only my first name, DECO, and my logo is Thrillers at the Speed of Light. Ooh. You are so on it.
Starting point is 00:15:20 What's the name of your book, hon? The Libra Affair. The Libra Affair. The Libra Affair. Libra, of course, is a constellation, one of the 12 of the traditional zodiac. Traditional, because they did change last year. Well, no, we've had 13 constellations forever in it. Oh, they just didn't mention it to other people? Every two years, people forget it and someone announces it and they think it's something new that got discovered. Wow.
Starting point is 00:15:39 And in fact, the symbol for pound in our world is what? Hashtag? No. Well, it can be that, but it's letters. It's what? LB. LB, which is Libra. Did you know that? Most people write LB all their whole lives and don't know that means Libra. I had no idea.
Starting point is 00:15:55 Yeah. You never stopped and thought, why does LB stand for pound? No, dude. I really didn't. Because Libra is the scales. I had other fish to fry. Libra is the scales. And Libra is the constellation in the sky that has the star names that are the longest of all the others.
Starting point is 00:16:09 How about that? Yeah. You would be hella great on Jeopardy. No, no. So I'm going to tell you. So two of the stars in the constellation Libra, one is Zubin El Janubi and the other one is Zubin Eshamali. Wow. Zubin El Janubi?
Starting point is 00:16:21 Zubin El Janubi and Zubin Eshamali. Someone who listens to this show is naming their twins this as we speak. And it's your fault. So when you grew up, Dako, were you beaten up by other girls? Well, they didn't beat me up. They were afraid of me because I was so unique. I had this unique name. She's the speed of light.
Starting point is 00:16:43 How could they catch you? That's right. They couldn't catch me. You got it. Well, I'm going to keep working on your thing. Now, did you have a question, or was your question what was the meaning of your name? I wanted to see if you could figure out what my name meant. Okay, I think I can do better than just representing them as single symbols, because maybe they come together in some important way.
Starting point is 00:17:01 Well, that would be interesting, because I've got on my website this meaning, and if I'm wrong, boy, I need to correct that. Let me see if I can... I've got the whole literary world believing that I'm the speed of light. No, we can still get the speed of light in there because C is the speed of light. We're not going to argue that. Okay. Let me work on it, and we'll get back to you. Okay, super. Thank you so much for taking my call. Well, happy to... It's so much fun. Happy to have you on. Well, thanks for calling StarTalk, the Cosmic Queries edition. So, Leanne. Yes. Yeah, so what was your mother smoking when she named you?
Starting point is 00:17:36 Listen, ask what my dad would smoke, because this is what happens when you let fathers name their kids. Oh, is that what that is? Yes. My dad was a big fan of Vivian Leigh. That's how I got the L-E-I-G-H. And then they just threw tactile on the end so people think I'm from the South. And I'm not. Yeah, Leanne with your accent.
Starting point is 00:17:53 But you're from Brooklyn or something, right? I'm from Queens. Queens. Excuse me. Yeah. Come on. Get it right now. So we got like 15 seconds.
Starting point is 00:18:01 Is there a 15 second question there? No, man. There's really not. These are emails. People did not feel constrained in any way. We have novel 15 seconds. Is there a 15-second question there? No, man. There's really not. These are emails. People did not feel constrained in any way. We have novel-sized questions here. Oh, because if it came over Twitter, they'd contain it in 140 characters. They would contain themselves.
Starting point is 00:18:13 Email, people are not containing themselves. All right. Well, we'll get back to a longer question on the cosmos in the Cosmic Queries edition right after this. We're back to the Cosmic Queries of StarTalk. I'm Neil deGrasse Tyson. Leanne. Leanne Lord is here. Leanne Lord, how are you?
Starting point is 00:18:49 I'm excellent. How are you? All right. Well, you were reading me questions before the break. I was. Called from, in this case, email, right? Yes. You know where they're from? Sometimes they tell us where they're from.
Starting point is 00:18:56 Well, actually, yes. I do have someone who has emailed us from Barcelona. Barcelona. Barcelona. Yeah. Yes. They have the lift. Yes.
Starting point is 00:19:04 And this is from Joan. Beautiful city, of course. Of course. Yeah. Yes, they have the lift. Yes. And this is from Joan. Beautiful city, of course. Of course. Yeah. I wouldn't know. You got to get out. I don't get out. No, I get out.
Starting point is 00:19:11 I just haven't been there. Okay. I haven't been there. This is from Joan. Joan Genpere or Genpere. I'm not sure. And she says, congratulations on this great show. And it makes my daily two-hour train trips to work a lot easier so we're helping people
Starting point is 00:19:25 on their commute now she says that uh some time ago stephen hawking said that in a contact with an advanced civilization uh it could turn very bad for us same as when europeans went to america so can the potential risks of contacting an alien civilization somehow be evaluated? I guess that according to the history of only advanced civilization that we know so far, it doesn't look pretty for us. Yeah. So, all of our worries derive entirely from the fact that anytime we did that, we totally messed over the folks that we came upon. Just a bit. And the analogy here is that if anybody visits us, that means they crossed the vast emptiness of space in some kind of vehicle that is beyond our capacity to accomplish.
Starting point is 00:20:19 Right. Because we're not doing that. Right. Which would make them more advanced than we are. Mm-hmm. They're not coming over in Range Rovers, is what they're saying. A. Right. Which would make them more advanced than we are. Mm-hmm. A. They're not coming over in Range Rovers is what they're saying. A. B.
Starting point is 00:20:28 Now they come over. In all the cases where the Europeans went to the New World, they had greater technologies than the people they came upon. Mm-hmm. And it's always been bad for the people with the lesser technologies. So the fear factor that Stephen Hawking is expressing is more a fear of how he knows we would treat other people than it is from any actual knowledge of how an actual alien would treat us. So, in fact, he's holding up a mirror to our own cultures and our own motivations. So it's transference. We're assuming they're going to act like we are. I didn't know there was such a word.
Starting point is 00:21:02 Sure. The psychology talk? Transference? Yeah. Just a little bit. There. Transference. I didn't know there was such a word. Sure. The psychology talk? Transference? Yeah. Just a little bit. There. Transference. I'll go with that.
Starting point is 00:21:08 That's what it was. I co-host a psychology show, so I learned some stuff over there and bring it here. All right. Okay. Next one. Our next question is from Amiri. I hope I'm saying your name correctly. And she says, Dr. Tyson's explanation of how we could move.
Starting point is 00:21:24 How do you know it's a she? I don't. You're assuming it. I am i am just make that clear go on okay so it wants to know it's okay dr tyson's explanation of how we could move uh incoming meteorites by parking a satellite next to it uh lock them by gravity then slowly tug them out of its trajectory got me to ask, what would it take to do something similar to planets? Like, could we move some of the planets to the Goldilocks zone? Would it mess up the orbits of Earth or Mars? Excellent question. So that would be sort of planetary engineering.
Starting point is 00:22:00 Yes. Right. Oh, there's a planet we want to live on. If it's too close or it's too far away, let's move it to the Goldilocks zone where the temperature from the sun is just right for liquid water as opposed to frozen water or evaporated water. We have words for those, ice and steam, right? Or vapor. Wait, let me write that down. I've learned so much here. Ice, how do you spell that? So the day that we can start shifting planetary bodies around like asteroids and then large asteroids, start small, work big.
Starting point is 00:22:29 I don't see any reason why we can't just start shifting planets around. You have to be careful because if planets get too close to one another, they create what are called resonances. And when you have a resonance, it means one planet does not orbit freely. It's locked in place relative to another planet. And when that happens, or their orbital periods are locked relative to one another. And so there are these weird gravitational sort of resonances out there that you want to watch out for because some of them are unstable and you can be flung out of the solar system entirely.
Starting point is 00:23:03 In fact, the early solar system, we've hypothesized justifiably that we might've had 20, 30, 50 planets to start out in our solar system. Because you know what happens? If you create a solar system on a computer and give it 50 planets and let it just fight it out, you get like a few planets left after a billion years or so. And the rest are cast into interstellar space. And they're called rogue planets. And in fact, there may be more rogue planets, homeless planets in the galaxy than planets that actually orbit actual stars. Homeless planets.
Starting point is 00:23:40 Homeless planets. And so, yeah, I mean, nature does a lot of moving planets around. There are solar systems, star systems where Jupiters are close to the host star. Our Jupiter is far away, and we've got Mercury, Venus, Earth, and Mars between Jupiter and our sun. There are other solar systems where their Jupiter-sized object is really close. We think that Jupiter migrated inward, flinging other planets out. Out of my way. I need to be near the star. Exactly.
Starting point is 00:24:05 It's a diva planet. Exactly. That's what we should call them, diva planets. Diva planets. That's a new one. You heard it here first. We'll start it here first on StarTalk. Cosmic queries.
Starting point is 00:24:15 We've got time for one more question in this segment. What do you got? You know what? This sort of comes off from the same person, off of the same theory. Could we move Mercury and Venus, and how long would it take to cool them down sufficiently to terraform oh uh things cool off pretty quickly oh venus is nine like a relationship not venus is hot enough to like melt lead and zinc and i calculated it would cook nine seconds to take nine seconds to cook a pizza on your windowsill but then a geekier person than i am corrected me and
Starting point is 00:24:46 said, no, you left out the radiative effects of the atmospheric, the thermal, and so it actually would take a fraction of a second to cook. When we come back, more on cooking pizza on Venus. Cognac Queries after hour. We're back on StarTalk Radio. I'm Neil deGrasse Tyson.
Starting point is 00:25:20 Leanne Lord is with me. Yes, I am. Co-hosting. Co-hosting. My favorite job. Comedian. We're your favorite. You say that in all your me. Yes, I am. Co-hosting. Co-hosting. My favorite job. Comedian. We're your favorite. You say that in all your gigs.
Starting point is 00:25:28 No, that's not true. I love you guys. Because we have the best fans. They tweet me so much. It's fantastic. Excellent. Because we're in your stream. Yes. Yeah, good.
Starting point is 00:25:37 So we left off talking about a great question. What happens? Cooking pizza. Move Mercury and Venus, I presume farther away, to make them habitable. Right, to terraform. And they know Venus is very hot, Mercury is very hot. Bring them farther away from the sun so the sun's rays are less intense. And bring them into the Goldilocks zone.
Starting point is 00:25:55 Here's a problem with Venus. Venus is hot only in part because it's near the sun. It's especially hot because it has a runaway greenhouse effect. There's something about the carbon dioxide you're going to have to fix before you want to live on Venus. So it's a fixer-upper planet. It's a total fixer-upper planet. CO2 is 98% of the atmosphere and it's very dense. 100 times the atmospheric pressure on Venus as it is here on Earth.
Starting point is 00:26:21 It's probably closer to 90, but I round it to 100. Back of the envelope equation. Back of the envelope equation. Back of the envelope. Yeah, just round it. Because the difference between 90 and 100 is not important for the point I'm making. So I just round it to 100. And so it's about 100 times the atmospheric pressure that we have here on Earth. So you step out on Venus, you'll be crushed and vaporized simultaneously.
Starting point is 00:26:44 But I'll look good. Because I'll be a lot slimmer for like a half a second. So you need to not only fix the CO2 problem, which is a greenhouse gas, as we all know, but also when you do that and then you let the planet cool down, that shouldn't take too long because it'll just radiate out into space. Look how fast Earth cools on a hot day after sunset in the desert. Okay.
Starting point is 00:27:08 If you go to the desert, right, if it's dry, because actually moisture is a greenhouse gas itself, that's why in wet places you don't get high temperature extremes, but in deserts you do. It warms up in the daytime. Right. There's nothing to trap the heat. There's certainly no carbon dioxide and no water vapor.
Starting point is 00:27:28 The heat escapes rapidly. Temperature drops 20, 30 degrees within a few hours. You know what? I always wondered that. That's why the deserts have huge temperature extremes and other places. Hawaii does not. Okay.
Starting point is 00:27:39 Completely surrounded by water. Now, is that because the really hottest part of the day is really the end of the day? You still have that heat being released? The hottest part of the day is really the end of the day? You still have that heat being released? The hottest part of the day is when the sun's rays are its most intense. Well, that would be high noon. However, there's a time delay. That's when the sun's rays are most intense hitting Earth.
Starting point is 00:27:58 Right. But the sun does not heat the air. The sun heats the ground. The ground heats the air. Okay. So there's a time delay between that that takes one or two hours. That's why the hottest time of day is two or three in the afternoon. Ah, that's what I was thinking of. You're most susceptible to sunburn is at high noon when the sun has its most direct
Starting point is 00:28:21 rays on you. So that's this time delay. And that's why the hottest month of the year is not June. No. Even though the sun is at its highest at any location on Earth, it's at its highest in that month. It takes a couple of months for the heat to hit the Earth and build up back and then warm the atmosphere.
Starting point is 00:28:39 So visible light hits Earth, heats it. Earth re-radiates that same energy as infrared, and it's the infrared that gets trapped by the greenhouse gases. If greenhouse trapped visible light, the visible light would never reach Earth's surface. It would trap it in midair. This is why we receive energy from the sun and then keep it with the greenhouse effect. Because most of the energy that we that becomes the greenhouse started out as visible light it's very cool you're good that's right no no it's the universe
Starting point is 00:29:10 it's the universe that's good well no i mean the way it's not only good it's like no no you're fantastic yeah so uh stuff cools pretty quickly that's not the problem okay yeah what else you got uh all right i have a question um i don't have a name uh this person is shy an anonymous email well i i can say this they're from a school because they're it's a dot edu so it's a student institutional institution yes i'm just putting on my csi cap here and they want to know who uh was our most scientifically friendly president like which one of our u.s presidents was the most friendly to the field of science ever yeah it depends on what you mean by friendly. In Washington, friendly means how much money do you give the enterprise.
Starting point is 00:29:49 That's what, in Washington, all that matters is money. What you say doesn't matter at all. Okay. Okay. Then let's go. Just an FYI. Got you. Okay.
Starting point is 00:29:58 All right. So a few things. Abe Lincoln began the National Academy of Sciences. Now that's kind of cool. Very. It was set up to establish an advisory board to Congress that was not itself politically motivated for any reason. And so Congress would call on the National Academy of Sciences to produce studies on scientific issues that befall the day.
Starting point is 00:30:27 I got to put Lincoln at the top of that list. Okay. As the most scientifically aware and literate. So he was not just a cat owner. I didn't know he owned cats. He was the first president to have a cat. I did not know. Why do you even know that?
Starting point is 00:30:39 Because I was getting tired of the slavery thing. Like, what else did he do? When we come back, of cosmic queries on star talk star talk cosmic queries leanne lord with me here in studio StarTalk Cosmic Queries. Leanne Lord with me here in studio. You didn't say my favorite line. What is that? StarTalk Cosmic Queries after dark.
Starting point is 00:31:13 It exists in the dark. So we left off talking about Link. The question was, who's the most science-friendly president? Yes. And I'd have to say, given all the things that presidents have done, you know, Jefferson was quite scientifically literate. Yes. money to science because science was viewed as an engine of our national security. So it wasn't so much that they were curious about the frontier, but just that science was good for war, essentially, and for winning wars. But Lincoln, there's another bit about Lincoln. You read the Gettysburg Address?
Starting point is 00:31:58 I read Abraham Lincoln. Don't say um. Don't start that with an um. I read Abraham Lincoln, Vampire Hunter. Okay. I think they covered it. A Gettysburg Address. I don't memorize the whole thing.
Starting point is 00:32:06 But four score and seven years ago, our forefathers brought forth a new nation conceived in liberty. It goes on like that. If you feel the rhythm of it, it's five, six, seven words at a time. And that's like the right number of words for an attention span if you're listening to someone speak. Think about that. Okay. Yeah. And then I thought about it and I said, why is this speech so effective?
Starting point is 00:32:30 Of all the speeches given by all the politicians, this one is up on the wall and there are no complex sentences within it. If you take a quill pen and dip it, you have about as much ink as will get you five, six, seven words. Yeah. And it occurred to me that feather pen writing of speeches forces a rhythm in your communication that is the perfect marriage of words on a page and words to the ear. So to this day, when I'm preparing an important speech, I will write that speech with a quill pen. Or I will dip my fountain pen unfilled. The fountain pens can store ink. Yes.
Starting point is 00:33:13 So that doesn't count. It's unlimited ink until you run out. I will not fill it, and I will dip it in a well, and I will write it out that way. And that forces me to contain the ideas in morsels, in parcels of information, which then is my hope that the listener will embrace. Love it. And so I have a collection of fountain pens and quill pens. I do too. I just go there.
Starting point is 00:33:35 I'm a pen person. That's just what I do. We've talked about this. And sometimes I go all the way. If I'm writing with a quill pen, I like candles because that's how. Well, that's how it should be done. That's how. If you're going to go there.
Starting point is 00:33:44 Do you put on the powdered wig? I need a picture of you in the powdered wig. This is fantastic. No, I don't do wig. Come on now. Then you're not doing it the whole way. Oh, come on. So now we're going on to Cosmic Query's lightning round.
Starting point is 00:33:58 Lightning round. Let me get the bell. Test it. There we go. All right. Let's do this, Leanne. All right. Lightning round.
Starting point is 00:34:04 My favorite. All right. This is from Mike Hall Leanne. All right, lightning round, my favorite. All right, this is from Mike Hall, and he wants to know, are there valuable resources that are easier to obtain from space than drilling into the Earth for? They're not easier to get to, but oh, so you want them. Because on Earth, we
Starting point is 00:34:19 fight wars over resources that are underfoot. We do. And the universe is an unlimited supply of all the resources that we fight each other to get down here on Earth. So whether or not they're easy to get, they're better to get. Next. Got it. All right.
Starting point is 00:34:33 Next question is from Chris Van Gundy. How can we determine the difference between a brown dwarf and a large rogue planet? Oh, it's hard. Brown dwarf is a star that didn't make it. And a large rogue planet is just a big old chubby planet. There are astrophysical differences between the two, but they're very hard to notice from a distance. So it's very hard. It's one of the big challenges.
Starting point is 00:34:54 And we got low-mass star people and high-mass planet people meeting in the dark of night trying to solve that problem. You said chubby planet. Next question is from Peter O'Hara. He says, can you give us your take on parallel universes? They sound really cool. I agree. Parallel universes are awesome. But you should think of them not as parallel to one another, but as the consequence of the multiverse.
Starting point is 00:35:16 In the multiverse, you have multiple universes popping out of some original distortion of the fabric of space and time. We are just one of multiple universes, hence the multiverse. And so there could be other universes adjacent to us in a higher dimension, and we would never know it. I think of them as parallel universes. Next. Nice. Joshua Jenkins wants to know, why does the Earth spin in the direction it does?
Starting point is 00:35:40 And what if Earth started spinning twice as fast as it does now? Okay, so we spin this direction because I'm going to say it exactly physically. You ready? Yes. That is the direction of the angular momentum of the entire solar system. So we're going with the flow. Beautiful. We're going with the flow.
Starting point is 00:35:57 The sun spins that way. All planets orbit that way. The moons orbit that way. Everybody is going counterclockwise as viewed from the top. Now, why do they want to spin up Earth? I don't know. That would have the length of the day. There would be 12-hour days instead of 24-hour days.
Starting point is 00:36:13 Oh, I can't get enough done. And the act of spinning us up, okay, we'll feel that. That would not be a good day on Earth, all right? Okay. You will know when Earth stars are spinning faster. Well, you know what will happen? Stuff behind you will run into you, and you'll be flattened against it, and you'll be a pile of goo on the wall behind you. Ew.
Starting point is 00:36:30 Because right now you're moving 800 miles an hour with the rotation of the Earth. If you all of a sudden start going 1,600 miles an hour, something came in behind you to push you to do that, and that will flatten you into a pile of goo. Next. Yeah, not with it. Fast. Brady, what would your opinion be on the seemingly regularity of mass extinctions on Earth? They're not really regular.
Starting point is 00:36:50 There's some analysis where you can see, oh, every 20 million years, things go extinct, but you have to cut the data in a way that makes it look that way. If you don't cut the data, the regularity is not really there. Okay. So extinctions happen kind of randomly,
Starting point is 00:37:03 and we're in the middle of what's called the sixth great extinction on Earth and that extinction is caused by humans. We gotta run. Oh.
Starting point is 00:37:12 Gotta go. That's it. Wow. Star Talk brought to you in part by the National Science Foundation, Landlord Great Avenue. Thank you.
Starting point is 00:37:19 I'm Neil deGrasse Tyson. As always, keep looking up.

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